A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

Rome’s legendary peephole vista is also a former Crusader stronghold.

Created as a punny statement about genetic engineering this monstrous hybrid statue has become a beloved icon.

A small village in two different countries.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

Macabre astrological automaton clock dating to the late 1400s.

A mud brick kasbah with a history of lavishness and traitorship.

A fortified city, home to a remaining population of five families

Giant, friendly pelicans in Central London, the most unlikely of places.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

19th century museum with an eclectic mix of curiosities, from Egyptian artifacts to items on archery history to the skull of the world's oldest horse.

Several land speed world records were shattered at this Welsh beach.

A 19th-century funicular railway shuttles visitors up this surprising sea cliff to one of the world's largest camera obscuras.

A tiny village in Wales claims the name of a noble medieval hound slain for a crime he didn't commit.

The longest and tallest aqueduct in Britain can actually be sailed across.

A former fisherman's hut deemed too small for habitation is now a delightful tourist draw.

A hidden tunnel leads to an abandoned slate quarry that's now a secret swimming spot guarded by cliffs.

The highest peak in Wales is said to be the final resting place of a giant killed by King Arthur.

A subterranean playground in an abandoned slate mine.

The decaying ruins of Wales' first asylum for the mentally ill.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

A tiny church on a man-made island in the Adriatic.